I’m one among many I know who upgraded my work system from Windows 7 to Windows 10 and regret it even after a year! The upgrade process was smooth, but every once in a while, it won’t allow me to login - it will just repeatedly throw an error saying my credentials are invalid (though they’re not). The solution is to try switching login methods, turn off the network, wait for several minutes or some combination of these. The number of times I’ve been away, returned to my system to get into a Skype for Business call, only to find I can no longer unlock my system is not even remotely funny anymore. I have learned to be around several minutes before any call so I can fight, if necessary, to get in! I’ve read forum posts on many sites, but don’t have any solutions. My system is set to auto-update Windows. So it’s not that I’m not on the latest or that MS has fixed it.

So no, there are very, very good reasons, IMO, to stay on Windows 7 or 8.1 (where this problem didn’t exist). I actively recommend others not to switch to Windows 10 because of this. Of course, YMMV!